U.S. Rep. Dan Lipinski and challenger Marie Newman on Wednesday night traded barbs over social issues and the best way to get things done in Washington in the only debate of a congressional race that’s drawn a national spotlight as a stand-in for the Democratic Party’s future.

First-time candidate Newman repeatedly criticized the seven-term Lipinski for social positions that she said are too conservative for the 3rd District, which takes in a swath of the Southwest Side bungalow belt and dips deep into the south and southwest suburbs.

“He sponsored (the Religious Freedom Act) because he’s anti-LGBTQ, and I’m just going to play that exactly as it is, because he is,” Newman said.

Lipinski, a former university professor who succeeded his long-serving father in the congressional seat, cast himself as the pragmatist who takes common-sense positions for constituents who want him to get things done.

“A lot of things that Ms. Newman talks about, she plays that somehow it’s going to magically happen,” he said. “What we need to do is sit down and work out some compromise. Compromise has become a dirty word in Washington. The Tea Party, the Freedom Caucus are a major problem. Having a Tea Party of the left that makes promises about all these things that can happen magically, it’s not going to work.”

The forum at Moraine Valley Community College in Palos Hills was packed as a crowd that the League of Women Voters pegged at 568 people cheered, booed and shouted back at the candidates as they answered questions submitted via email ahead of time and on slips of paper at the event.

The format discouraged direct back-and-forth between the two, with a moderator giving each a chance to respond to the same question before moving on to the next one. Nonetheless, there were several moments of testiness.

After getting a question about marijuana legalization, Lipinski said he was “looking forward to getting to questions relating to people’s everyday life here, and the bread-and-butter issues that most people in the 3rd District are concerned about.”

The contest is getting wider-than-usual attention in part because Newman’s attack on Lipinski’s positions against abortion rights and his votes against the Affordable Care Act and the DREAM Act to protect young undocumented immigrants come at a time of broader polarization within the party. Progressives, emboldened by Vermont U.S. Sen. Bernie Sanders’ strong showing in the 2016 Democratic presidential race, are seeking to oust more conservative congressmen and push the party to the left.

Service Employees International Union Illinois State Council has thrown its support to Newman, who has pledged to work for a $15 minimum wage. She’s also drawn headlines for endorsements from New York U.S. Sen. Kirsten Gillibrand, feminist icon Gloria Steinem and U.S. Reps. Jan Schakowksy of Evanston and Luis Gutierrez of Chicago, who took the unusual step of backing a challenger to one of their local Democratic colleagues.

The Illinois AFL-CIO is backing Lipinski, as is the American Federation of State, County and Municipal Employees Council 31, the United Steelworkers and various labor organizations representing transportation workers, a reflection of his status as the longest serving Illinoisan on the House Transportation and Infrastructure Committee.

The district is solidly blue, and the winner of the Democratic primary election has long been seen as the overwhelming front-runner to win the seat.

This year that might be even more true than usual. The lone candidate on the GOP primary ballot is Holocaust denier Arthur J. Jones of Lyons, who the Illinois Republican Party chairman has disavowed for his extremist views. Jones attended the Lipinski-Newman forum on Wednesday, standing near the back of the crowded room wearing a “Make America Great Again” hat.